* Copyright (c) 2011 The NetBSD Foundation, Inc.

/* $NetBSD: v7fs.h,v 1.4 2022/05/24 06:28:01 andvar Exp $ */

/*-
* Copyright (c) 2011 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by UCHIYAMA Yasushi.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/

#ifndef _V7FS_H_
/* 7th Edition of Unix(PDP-11) Filesystem definition. */
#define _V7FS_H_
#include <sys/types.h>
#ifndef _KERNEL
#include <inttypes.h>
#endif
/*
* V7 File System
*
* +------------------
* |Boot block (512byte) sector [0]
* |
* +------------------
* |Super block (512byte) sector [1]
* |
* +------------------
* |v7fs_inode(64byte sector [2]
* .
* .
* |
* +------------------
* |data block sector [datablock_start_sector]
* |
* .
* .
* |
* +------------------
* <- [sector volume_size]
*
* |
* +------------------ volume size.
*
* Max volume size is 8GB (24bit daddr_t)
* Max file size is ~1GB
*
*/

/* V7 type. */
typedef uint16_t v7fs_ino_t;
typedef uint32_t v7fs_daddr_t;
typedef int32_t v7fs_time_t;
typedef uint32_t v7fs_off_t;
typedef uint16_t v7fs_dev_t;
typedef uint16_t v7fs_mode_t;
#define V7FS_DADDR_MAX 0x00ffffff
#define V7FS_INODE_MAX 0xffff

#define V7FS_BSIZE 512
#define V7FS_BSHIFT 9
#define V7FS_ROUND_BSIZE(x) \
((((x) + (V7FS_BSIZE - 1)) & ~(V7FS_BSIZE - 1)))
#define V7FS_TRUNC_BSIZE(x) ((x) & ~(V7FS_BSIZE - 1))

#define V7FS_RESIDUE_BSIZE(x) \
((x) - ((((x) - 1) >> V7FS_BSHIFT) << V7FS_BSHIFT))

/* Disk location. */
#define V7FS_BOOTBLOCK_SECTOR 0
#define V7FS_SUPERBLOCK_SECTOR 1
#define V7FS_ILIST_SECTOR 2

/* Superblock */
/* cache. */
#define V7FS_MAX_FREEBLOCK 50
#define V7FS_MAX_FREEINODE 100
struct v7fs_superblock {
/* [3 ... (datablock_start_sector-1)]are ilist */
uint16_t datablock_start_sector;
v7fs_daddr_t volume_size;
int16_t nfreeblock; /* # of freeblock in superblock cache. */
v7fs_daddr_t freeblock[V7FS_MAX_FREEBLOCK]; /* cache. */
int16_t nfreeinode; /* # of free inode in superblock cache. */
v7fs_ino_t freeinode[V7FS_MAX_FREEINODE]; /* cache. */
int8_t lock_freeblock;
int8_t lock_freeinode;
int8_t modified;
int8_t readonly;
v7fs_time_t update_time;
v7fs_daddr_t total_freeblock;
v7fs_ino_t total_freeinode;
} __packed;

/* Datablock */
#define V7FS_NADDR 13
#define V7FS_NADDR_DIRECT 10
#define V7FS_NADDR_INDEX1 10
#define V7FS_NADDR_INDEX2 11
#define V7FS_NADDR_INDEX3 12
/* daddr index. */
#define V7FS_DADDR_PER_BLOCK (V7FS_BSIZE / sizeof(v7fs_daddr_t))
struct v7fs_freeblock {
int16_t nfreeblock;
v7fs_daddr_t freeblock[V7FS_MAX_FREEBLOCK];
} __packed;

/* Dirent */
#define V7FS_NAME_MAX 14
#define V7FS_PATH_MAX PATH_MAX /* No V7 limit. */
#define V7FS_LINK_MAX LINK_MAX /* No V7 limit. */
struct v7fs_dirent {
v7fs_ino_t inode_number;
char name[V7FS_NAME_MAX];
} __packed; /*16byte */

/* Inode */
#define V7FS_BALBLK_INODE 1 /* monument */
#define V7FS_ROOT_INODE 2
#define V7FS_MAX_INODE(s) \
(((s)->datablock_start_sector - V7FS_ILIST_SECTOR) * \
V7FS_BSIZE / sizeof(struct v7fs_inode_diskimage))
#define V7FS_INODE_PER_BLOCK \
(V7FS_BSIZE / sizeof(struct v7fs_inode_diskimage))
#define V7FS_ILISTBLK_MAX (V7FS_INODE_MAX / V7FS_INODE_PER_BLOCK)

struct v7fs_inode_diskimage {
int16_t mode;
int16_t nlink; /* [DIR] # of child directories. [REG] link count. */
int16_t uid;
int16_t gid;
v7fs_off_t filesize; /* byte */
#define V7FS_DINODE_ADDR_LEN 40
/* 39 used; 13 addresses of 3 byte each. */
uint8_t addr[V7FS_DINODE_ADDR_LEN];
/*for device node: addr[0] is major << 8 | minor. */
v7fs_time_t atime;
v7fs_time_t mtime;
v7fs_time_t ctime;
} __packed; /*64byte */

/* File type */
#define V7FS_IFMT 0170000 /* File type mask */
#define V7FS_IFCHR 0020000 /* character device */
#define V7FS_IFDIR 0040000 /* directory */
#define V7FS_IFBLK 0060000 /* block device */
#define V7FS_IFREG 0100000 /* file. */
/* Obsoleted file type. */
#define V7FS_IFMPC 0030000 /* multiplexed char special */
#define V7FS_IFMPB 0070000 /* multiplexed block special */
/* Don't appear original V7 filesystem. Found at 2.10BSD. */
#define V7FSBSD_IFLNK 0120000 /* symbolic link */
#define V7FSBSD_IFSOCK 0140000 /* socket */
/* Don't appear original V7 filesystem. NetBSD. */
#define V7FSBSD_IFFIFO 0010000 /* Named pipe. */

#define V7FSBSD_MAXSYMLINKLEN V7FS_BSIZE

#endif /*!_V7FS_H_ */